Summary of Significant Accounting Policies (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Other than Temporary Impairment Losses, Investments	$ 0	$ 0
Value of Stock Repurchased by FHLBP	288,000	577,000
Restricted stock	3,426,000	3,625,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Amount of Advances	20,000,000	20,000,000
Dividend Income	3,163,000	3,250,000
Federal Home Loan Bank, Advances, General Debt Obligations, Maximum Amount Available	178,200,000
Real Estate Acquired Through Foreclosure	1,100,000	3,800,000
Preferred Stock, Dividend Payment Rate, Variable	The dividend rate, which is calculated on the aggregate Liquidation Amount, was initially set at 3.874% per annum based upon the current level of "Qualified Small Business Lending", or "QSBL" (as defined in the Securities Purchase Agreement) by DNB's wholly owned subsidiary, DNB First, National Association (the "Bank"). The dividend rate for future dividend periods will be set based upon the "Percentage Change in Qualified Lending" (as defined in the Securities Purchase Agreement) between each dividend period and the "Baseline" QSBL level. Such dividend rate may vary from 1% per annum to 5% per annum for the second through tenth dividend periods depending on the volume of QSBL the Bank originates in future periods, and will be fixed at a rate between 1% per annum to 7% per annum and remain unchanged up to four and one-half years following the funding date (the eleventh through the first half of the nineteenth dividend periods). If the Series 2011A Preferred Stock remains outstanding for more than four-and-one-half years, the dividend rate will be fixed at 9%. Prior to that time, in general, the dividend rate decreases as the level of the Bank's QSBL increases.
Preferred Stock, Value, Outstanding	13,000,000
Investment in Federal Home Loan Bank Stock [Member]
Restricted stock	2,200,000
Dividend Income	$ 4,000
Series 2008A Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage		5.00%
Series 2011A Preferred Stock [Member]
Preferred Stock, Dividend Rate, Percentage	1.00%